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C Wesseling

Publications and source records attributed to C Wesseling.

13 recordsLinked to original sources
PubMed2001

Risk of pancreatic cancer in workers exposed to chlorinated hydrocarbon solvents and related compounds: a meta-analysis.

This is a meta-analysis of occupational exposures to chlorinated hydrocarbon (CHC) solvents and pancreatic cancer, based primarily on studies that addressed exposure directly (agent studies) and secondarily on studies that reported data without verification of individual CHC exposures (job title studies), all of which were listed in databases for the period January 1969 to May 1998. Standardized extraction of data and double-checking of consistency of data extraction by five extractors were done. Simple random models estimated meta-relative risks. Suggestive weak excesses were found for trichloroethylene (meta-relative risk (MRR) = 1.24, 95% confidence interval (CI): 0.79, 1.97), polychlorinated biphenyls (MRR = 1.37, 95% CI: 0.56, 3.31), methylene chloride (MRR = 1.42, 95% CI: 0.80, 2.53), and vinyl chloride (MRR = 1.17, 95% CI: 0.71, 1.91) but not for carbon tetrachloride. One study addressed tetrachloroethylene (MRR = 3.08, 95% CI: 0.63, 8.99); another investigated chlorohydrin production (MRR = 4.92, 95% CI: 1.58, 11.4). Exposure-response meta-analyses for trichloroethylene and methylene chloride failed to reveal trends. Job title studies on metal degreasing and dry cleaning revealed significant MRRs (2.0 and 1.4, respectively). Publication bias was unlikely. Confounding may have remained insufficiently controlled. Unless the results are seriously biased by exposure or endpoint misclassification or by confounding, strong causal associations between CHC compounds and pancreatic cancer can be judged unlikely. Interactions between environmental and occupational agents, lifestyle factors, and genetic susceptibility remain a possibility, but the data for this meta-analysis did not address interactions.

Canada↗
PubMed2001

Chronic nervous-system effects of long-term occupational exposure to DDT.

Dichlorodiphenyltrichloroethane (DDT) is a compound with moderate toxicity that is judged to be safe for occupational use, although little is known about its long-term effects on the human nervous system. We investigated chronic nervous-system effects of long-term occupational exposure to DDT by comparing the neurobehavioural performance of retired malaria-control workers with a reference group of retired guards and drivers. DDT-exposed workers did worse on tests assessing various neurobehavioural functions than controls; performance significantly deteriorated with increasing years of DDT application. Our results could not be explained by exposure to cholinesterase-inhibiting pesticides or other potential confounding factors.

Aged↗
PubMed1999

Geographical differences of cancer incidence in Costa Rica in relation to environmental and occupational pesticide exposure.

BACKGROUND: This study describes geographical differences in cancer incidence in Costa Rica, and investigates if some of these differences may be related to pesticides. METHODS: Data were combined from the cancer registry (1981-1993), the 1984 population census, the 1984 agricultural census, and a national pesticide data set. The 81 counties of Costa Rica were the units for the ecological analyses. Adjacent counties were grouped into 14 regions (3 urban and 11 rural) with relatively similar socioeconomic characteristics. County indices for population density and agricultural variables were constructed and categorized. Differences across regions and categories were assessed by comparing observed numbers of incident cases to expected values derived from national rates. Within the tertile of most rural counties, rate ratios between categories of high and low pesticide use were calculated. RESULTS: In urban regions, excesses were observed for lung, colorectal, breast, uterus, ovary, prostate, testis, kidney, and bladder cancers; and in rural regions for gastric, cervical, penile, and skin cancers. Skin cancers (lip, melanoma, non-melanocytic skin and penile cancer) occurred in excess in coffee growing areas with extensive use of paraquat and lead arsenate. In the most rural subset, heavy pesticide use was associated with an increase of cancer incidence overall and at a considerable number of specific sites, including lung cancer (relative risk [RR] 2.0 for men and 2.6 for women) and all female hormone-related cancers (RR between 1.3 and 1.8). CONCLUSIONS: Regions and populations at high risk for specific cancers were identified. Several hypotheses for associations between pesticides and cancer emerged. The findings call for studies at the individual level.

Confidence Intervals↗
PubMed1999

Collaboration between developing and developed countries and between developing countries in occupational health research and surveillance.

Collaborative occupational health and safety studies between counterparts in developing and developed countries and between developing countries have demonstrated their potential for improving occupational health and safety. Such collaboration in occupational health and safety is encouraged in the development of infrastructure in research empowerment and capacity building. This action includes the setting of priorities, the identification and documentation of problems, sponsorship, data bases and surveillance systems, technical support, methodology, publishing, research and training programs, controlled intervention, information exchange, and networking. Examples of priorities in occupational health and safety in the developing world include the informal sector (informally hired and independent workers), temporary work, pesticides, accidents, dusts, carcinogens, solvents, ergonomics, women and child labor, human immunodeficiency virus/acquired immunodeficiencey syndrome (HIV/AIDS), and transfer of hazardous materials and technologies. The sustainability of occupational health and safety structures and functions in the developing countries is a primary concern. Socioethical principles emphasize local, national, mutual and global gains. Examples of collaboration are given. Pervasive problems and strategies toward their solution are highlighted.

Developed Countries↗
PubMed1997

Unintentional fatal paraquat poisonings among agricultural workers in Costa Rica: report of 15 cases.

This study analyzes the exposure circumstances of 15 fatal occupational paraquat poisonings. To evaluate the potential danger of dermal absorption and the amount needed to produce a fatal outcome in the event of oral intake, we reviewed the medical records and autopsy protocols and interviewed relatives. Five fatalities were due to ingestion of a mouthful of paraquat concentrate, and five to intake of a smaller amount; three cases were associated with dermal exposure, and in two, there was no evidence of either oral or dermal exposure. Several cases concerned diluted paraquat spray. The clinical and pathomorphological findings, including a "blinded" evaluation of lung slides, were consistent with paraquat poisoning in all cases. Difficulties in establishing the diagnosis and recognizing the exposure were identified, as well as classification of unintentional poisonings as suicides at autopsy. The findings suggest that paraquat may cause fatal poisonings by ingestion of small amounts, by dermal absorption of diluted paraquat, and possibly by inhalation. More conclusive studies are warranted.

Administration, Oral↗
PubMed1997

Agricultural pesticide use in developing countries: health effects and research needs.

Large worker populations in the Third World are exposed to increasing amounts of pesticides, including pesticides severely restricted and banned in industrialized countries. Studies on knowledge, attitudes, and practices indicate that unsafe use of pesticides is the rule in Third World countries. Surveys of acute poisonings show high rates in these countries, despite underregistration. The scarce studies on chronic health outcomes demonstrate neurotoxic, reproductive, and dermatologic effects. Exposure assessment consists mainly of cholinesterase testing, and few studies have quantified dermal and respiratory exposure. The few intervention studies demonstrate the need for evaluation of the impact of preventive measures and policies. There is no evidence that widespread "safe-use" programs have greatly affected exposure and morbidity. It was concluded that research should focus on simple methods for surveillance of exposure and on surveillance of acute illness and its causes in order to develop and evaluate rapid local interventions. Studies on chronic effects should be carried out in selected countries, aiming at long-term and broader interventions. Policies that promote the use of pesticides should be critically evaluated. North-South and South-South research collaborations must be encouraged to address this global health problem.

Africa↗
PubMed1996

Cancer in banana plantation workers in Costa Rica.

BACKGROUND: Costa Rica has population and disease registries with potential value for epidemiological research. Pesticides have been intensively used on banana plantations, for example dibromochloropropane (DBCP). This study was planned to examine the quality of the cancer and civil registries and the feasibility of record linkages, and to explore cancer patterns among a highly exposed group. METHODS: A retrospective cohort study was carried out. Workers on the payrolls of banana companies, as reported to the Social Security System at any time between 1972 and 1979, were followed up in the cancer registry between 1981 and 1992: 29 565 men and 4892 women for 407 468 person-years. The observed cases of cancer were compared to the expected values, derived from the national incidence rates. RESULTS: We identified 368 cancer cases, 292 among men (standardized incidence ratio [SIR] = 76, 95% confidence interval [CI] 67-84) and 76 among women (SIR = 116, 95% CI: 90-142). Among men increased SIR were observed for melanoma (SIR = 197, 95% CI: 94-362) and penile cancer (SIR = 149, 95% CI: 55-324); among women for cervix cancer (SIR = 182, 95% CI: 122-241) and leukaemia (SIR = 274, 95% CI: 86-639). Risk estimates for lung cancer were evaluated among male workers with the longest time of employment. CONCLUSIONS: Follow-up was difficult due to deficient identification variables in the cancer registry and to easier identification of the living compared to the decreased in the civil registry at the end of the observation period. The various systematic errors in this study are likely to produce an underestimation of the relative risk estimates. This study contributes to improvements of the registries and increases the potential for cancer epidemiology in Costa Rica and other developing countries.

Adult↗
PubMed1996

Paraquat Exposure of Knapsack Spray Operators on Banana Plantations in Costa Rica.

A study of occupational exposure to paraquat was performed among 11 knapsack spray operators at banana plantations in Costa Rica. External and internal exposures were quantified and determinants of exposure identified by measurements, observations, and interviews. Dermal exposure was measured with skin pads, respiratory exposure by personal air sampling, and internal exposure by urine sampling. The wrists, back, and legs were the areas with the highest levels of dermal exposure. Respiratory exposures appeared to be strongly influenced by differences between days, while dermal exposures varied mostly due to differences between plantations. The use of protective clothing did not effectively protect against dermal exposures. Both respiratory and dermal exposures were significantly related to internal exposures, and both should be considered possible routes for systemic absorption of paraquat. It cannot be excluded that measurable levels of exposure can lead to acute as well as chronic health effects. Furthermore, due to poor conditions within the working environment, the spray operators are continuously at risk for high exposures that could lead to severe intoxication, and therefore a strategy for control of exposure is necessary.

Journal Article↗
PubMed1993

Pesticide poisonings in Costa Rica.

A descriptive epidemiologic study, conducted in Costa Rica, investigated the incidence of pesticide poisonings with special attention to agricultural workers and occupational exposure. Information from three national registers (occupational accident and disease reports, hospitalizations, and deaths) were used. During 1986, 1800 occupational accidents caused by pesticides were reported; between 1980 and 1986 altogether 3330 persons were hospitalized and 429 died. Cholinesterase inhibitors caused 71% of the reported occupational accidents, 63% of the hospitalizations, and 36% of the deaths. Paraquat caused 21% of the occupational accidents, 24% of the hospitalizations, and 60% of the deaths. Hospitalizations and deaths were 13 and 11 times, respectively, more frequent among agricultural workers than among the rest of the population. High-risk groups for occupational poisonings included agricultural workers aged 15-29 years, female workers, and banana plantation workers. The yearly incidence of symptomatic occupational pesticide poisonings among agricultural workers was estimated at 4.5%.

Adolescent↗
PubMedDate not supplied

Pesticide-related illness and injuries among banana workers in Costa Rica: a comparison between 1993 and 1996.

An intervention program considerably decreased systemic poisonings on banana plantations in Costa Rica in the early 1990s. Nevertheless, pesticide safety continues to be controversial. To examine the determinants of acute pesticide-related illness on banana plantations, the authors surveyed occupational injuries and illness among banana workers in the Atlantic Region of Costa Rica that were reported during 1993 and 1996 to the National Insurance Institute. Incidence rates were calculated for categories of pesticides and types of medical problems, for all and subgroups of banana workers. Between 1993 and 1996, an overall 35% decrease in injuries was observed, attributable to a marked decline in topical injuries (3.3 vs 1.9 per 100 workers), whereas systemic poisonings remained the same (0.7 per 100 in both years). The decrease concerned selectively milder skin conditions, indicating underreporting of less severe health effects. In both years, paraquat was the pesticide most frequently associated with injuries, mostly skin and eye lesions. Workers at highest risk per unit time of exposure were nematocide applicators, herbicide applicators, and cleaners of packing plants. Despite control measures, further reduction of systemic illness had not been achieved. The decrease of topical injuries may be partly explained by improved work conditions, but possible underreporting hinders interpretation. Pesticide-related illness on banana plantations is a persistent problem.

Accidents, Occupational↗
PubMedDate not supplied

Experiences from long-term research cooperation between Costa Rican, Nicaraguan, and Swedish institutions.

This paper summarizes experiences from long-term ongoing cooperation between Swedish research institutions and institutions at the National Universities in Nicaragua and Costa Rica. 24 researchers and teachers from the Central American institutions and ten Swedish research students have been trained. In addition to three full doctoral and three licentiate (two-year PhD program) theses, the two programs have so far published 15 articles in English-language, international, refereed journals and about three times as many abstracts for conferences in more than ten countries. A "sandwich" model for training is recommended, where the southern researchers come to the wealthier partner for collaborative analyses and write-ups of the publications, while spending 50-75% of their time in their home countries for data collection. Such collaboration should be planned for a time span of at least eight years and include substantial numbers of researchers and students. Means to minimize the risk of brain drain are suggested. The collaboration has been important for the globalization of the research cultures at the participating institutions and has trained international experts.

Costa Rica↗
PubMedDate not supplied

Time trends of occupational pesticide-related injuries in Costa Rica, 1982-1992.

To evaluate time trends of occupational pesticide-related injuries in Costa Rica, a survey was carried out three times over a ten-year period at a national reporting system for occupational accidents and diseases among wage-earning workers. The sample comprised the accidents reported during the months of June of the years 1982, 1987, and 1992. The overall incidence rates were 1.8, 2.7, and 2.5 per 1,000 agricultural workers, respectively. Rates among female workers increased (3.1, 3.7, 5.4) and were elevated as compared with male workers (1.7, 2.6, 2.3). The trend for topical lesions was upgoing (1.2, 1.4, 2.1), consistent with an increased use of fungicides and lack of safety measures for pesticides with low acute toxicity. Systemic poisonings peaked in 1987 (0.6, 1.2, 0.5), declining in 1992 with increased use of biologic pest control and pyrethroid insecticides less toxic than cholinesterase inhibitors, and improved safety during nematocide applications on banana plantations. In 1992, despite the largest decline of systemic poisonings in the banana-producing Atlantic Region, poisonings as well as topical injuries were still four times more frequent in this region than in the rest of the country. Restriction of highly toxic pesticides together with implementation of occupational safety measures can reduce systemic poisonings in developing countries. Such policies need to be extended to other pesticides to prevent less life threatening but often disabling skin and eye injuries.

Accidents, Occupational↗